VM host: dual CPU vs single CPU - same CPU performance rating
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I'm setting up a VM host and I was wondering if there are any advantages having two CPUs versus one if they have about the same number of cores and passmark cpu rating?
Right now I'm only setting up an older system for test so the question is a bit hypothetical at this point.
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You mean one or two physicals?
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@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
I'm setting up a VM host and I was wondering if there are any advantages having two CPUs versus one if they have about the same number of cores and passmark cpu rating?
Right now I'm only setting up an older system for test so the question is a bit hypothetical at this point.
There can be benefits, but it often is a wasted cost if you don't need that many cores or power.
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Example...
1x Eight Core CPU vs 2x Four Core CPU
All with the same clock speed?
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Depends on the CPUs. Single CPU means drastically lower power consumption, and faster inter-process communications.
Dual CPUs means more cache and more memory buses. But jumps you to NUMA.
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@scottalanmiller said in VM host: dual CPU vs single CPU - same CPU performance rating:
Example...
1x Eight Core CPU vs 2x Four Core CPU
All with the same clock speed?
Yeah, something along that line.
I usually use passmarks cpu benchmarks to roughly compare performance. In these tests dual CPUs never give the twice the performance of the same single CPU.
But for instance in my case 2 x E5-2630V2 (2x6 cores @ 2.5GHz) shows up as having about the same benchmark performance (single thread and multi thread) as 1 x E5-2670V2 (10 cores @ 2.5Ghz).
Comparing typical TDP: 2x6 cores is 2x80W=160W while 1x10 core is 115W.
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@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
I usually use passmarks cpu benchmarks to roughly compare performance. In these tests dual CPUs never give the twice the performance of the same single CPU.
Not a good test, but it's true, single CPU should be better at pure CPU tasks. But worse at memory ones.
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@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
But for instance in my case 2 x E5-2630V2 (2x6 cores @ 2.5GHz) shows up as having about the same benchmark performance (single thread and multi thread) as 1 x E5-2670V2 (10 cores @ 2.5Ghz).
Comparing typical TDP: 2x6 cores is 2x80W=160W while 1x10 core is 115W.
This is partly why I push companies so hard to move to single proc servers. Often makes far more sense. There is way less overhead.
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@scottalanmiller said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
But for instance in my case 2 x E5-2630V2 (2x6 cores @ 2.5GHz) shows up as having about the same benchmark performance (single thread and multi thread) as 1 x E5-2670V2 (10 cores @ 2.5Ghz).
Comparing typical TDP: 2x6 cores is 2x80W=160W while 1x10 core is 115W.
This is partly why I push companies so hard to move to single proc servers. Often makes far more sense. There is way less overhead.
But in this case tool six scores versus Single Tencor you might as well get the dual processor advantages since you’re going to have to pay for the licensing anyway if he runs any Microsoft products at all
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Thanks guys.
I decided to go with the single 10-core CPU in this case as it would leave open the possibility of adding another CPU and set of memory if needed.
No licensing to consider in this particular case.
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@jaredbusch said in VM host: dual CPU vs single CPU - same CPU performance rating:
@scottalanmiller said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
But for instance in my case 2 x E5-2630V2 (2x6 cores @ 2.5GHz) shows up as having about the same benchmark performance (single thread and multi thread) as 1 x E5-2670V2 (10 cores @ 2.5Ghz).
Comparing typical TDP: 2x6 cores is 2x80W=160W while 1x10 core is 115W.
This is partly why I push companies so hard to move to single proc servers. Often makes far more sense. There is way less overhead.
But in this case tool six scores versus Single Tencor you might as well get the dual processor advantages since you’re going to have to pay for the licensing anyway if he runs any Microsoft products at all
It seems to me, in these situations, software dictates hardware configuration negatively. That is frustrating if one wants to continue to use MS products. Choices, choices, choices!!
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@pmoncho said in VM host: dual CPU vs single CPU - same CPU performance rating:
@jaredbusch said in VM host: dual CPU vs single CPU - same CPU performance rating:
@scottalanmiller said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
But for instance in my case 2 x E5-2630V2 (2x6 cores @ 2.5GHz) shows up as having about the same benchmark performance (single thread and multi thread) as 1 x E5-2670V2 (10 cores @ 2.5Ghz).
Comparing typical TDP: 2x6 cores is 2x80W=160W while 1x10 core is 115W.
This is partly why I push companies so hard to move to single proc servers. Often makes far more sense. There is way less overhead.
But in this case tool six scores versus Single Tencor you might as well get the dual processor advantages since you’re going to have to pay for the licensing anyway if he runs any Microsoft products at all
It seems to me, in these situations, software dictates hardware configuration negatively. That is frustrating if one wants to continue to use MS products. Choices, choices, choices!!
I would say the software isn't dictating the hardware, but the licensing terms that comes with the software is.
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@dustinb3403 said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pmoncho said in VM host: dual CPU vs single CPU - same CPU performance rating:
@jaredbusch said in VM host: dual CPU vs single CPU - same CPU performance rating:
@scottalanmiller said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
But for instance in my case 2 x E5-2630V2 (2x6 cores @ 2.5GHz) shows up as having about the same benchmark performance (single thread and multi thread) as 1 x E5-2670V2 (10 cores @ 2.5Ghz).
Comparing typical TDP: 2x6 cores is 2x80W=160W while 1x10 core is 115W.
This is partly why I push companies so hard to move to single proc servers. Often makes far more sense. There is way less overhead.
But in this case tool six scores versus Single Tencor you might as well get the dual processor advantages since you’re going to have to pay for the licensing anyway if he runs any Microsoft products at all
It seems to me, in these situations, software dictates hardware configuration negatively. That is frustrating if one wants to continue to use MS products. Choices, choices, choices!!
I would say the software isn't dictating the hardware, but the licensing terms that comes with the software is.
You are correct. I re-typed that a couple different times and forgot the word "licensing" in the final reiteration.
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@pmoncho said in VM host: dual CPU vs single CPU - same CPU performance rating:
@dustinb3403 said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pmoncho said in VM host: dual CPU vs single CPU - same CPU performance rating:
@jaredbusch said in VM host: dual CPU vs single CPU - same CPU performance rating:
@scottalanmiller said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
But for instance in my case 2 x E5-2630V2 (2x6 cores @ 2.5GHz) shows up as having about the same benchmark performance (single thread and multi thread) as 1 x E5-2670V2 (10 cores @ 2.5Ghz).
Comparing typical TDP: 2x6 cores is 2x80W=160W while 1x10 core is 115W.
This is partly why I push companies so hard to move to single proc servers. Often makes far more sense. There is way less overhead.
But in this case tool six scores versus Single Tencor you might as well get the dual processor advantages since you’re going to have to pay for the licensing anyway if he runs any Microsoft products at all
It seems to me, in these situations, software dictates hardware configuration negatively. That is frustrating if one wants to continue to use MS products. Choices, choices, choices!!
I would say the software isn't dictating the hardware, but the licensing terms that comes with the software is.
You are correct. I re-typed that a couple different times and forgot the word "licensing" in the final reiteration.
Sure that's true - but only on the minimum side. i.e. Windows licensing defaults to dual 8 core setups. IF you need more than that - you have to buy more.
Buying a single 10 core machine that will run Windows means if you ever need a second processor in there - you'll be required to buy 2 more two core license packs. Something to consider.
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@dashrender said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pmoncho said in VM host: dual CPU vs single CPU - same CPU performance rating:
@dustinb3403 said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pmoncho said in VM host: dual CPU vs single CPU - same CPU performance rating:
@jaredbusch said in VM host: dual CPU vs single CPU - same CPU performance rating:
@scottalanmiller said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
But for instance in my case 2 x E5-2630V2 (2x6 cores @ 2.5GHz) shows up as having about the same benchmark performance (single thread and multi thread) as 1 x E5-2670V2 (10 cores @ 2.5Ghz).
Comparing typical TDP: 2x6 cores is 2x80W=160W while 1x10 core is 115W.
This is partly why I push companies so hard to move to single proc servers. Often makes far more sense. There is way less overhead.
But in this case tool six scores versus Single Tencor you might as well get the dual processor advantages since you’re going to have to pay for the licensing anyway if he runs any Microsoft products at all
It seems to me, in these situations, software dictates hardware configuration negatively. That is frustrating if one wants to continue to use MS products. Choices, choices, choices!!
I would say the software isn't dictating the hardware, but the licensing terms that comes with the software is.
You are correct. I re-typed that a couple different times and forgot the word "licensing" in the final reiteration.
Sure that's true - but only on the minimum side. i.e. Windows licensing defaults to dual 8 core setups. IF you need more than that - you have to buy more.
Buying a single 10 core machine that will run Windows means if you ever need a second processor in there - you'll be required to buy 2 more two core license packs. Something to consider.
Not a consideration in my book.
No one buys a machine and then adds a processor later.
They buy a box without spec'ing it right and then bitch about it not working well.
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@dashrender said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pmoncho said in VM host: dual CPU vs single CPU - same CPU performance rating:
@dustinb3403 said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pmoncho said in VM host: dual CPU vs single CPU - same CPU performance rating:
@jaredbusch said in VM host: dual CPU vs single CPU - same CPU performance rating:
@scottalanmiller said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
But for instance in my case 2 x E5-2630V2 (2x6 cores @ 2.5GHz) shows up as having about the same benchmark performance (single thread and multi thread) as 1 x E5-2670V2 (10 cores @ 2.5Ghz).
Comparing typical TDP: 2x6 cores is 2x80W=160W while 1x10 core is 115W.
This is partly why I push companies so hard to move to single proc servers. Often makes far more sense. There is way less overhead.
But in this case tool six scores versus Single Tencor you might as well get the dual processor advantages since you’re going to have to pay for the licensing anyway if he runs any Microsoft products at all
It seems to me, in these situations, software dictates hardware configuration negatively. That is frustrating if one wants to continue to use MS products. Choices, choices, choices!!
I would say the software isn't dictating the hardware, but the licensing terms that comes with the software is.
You are correct. I re-typed that a couple different times and forgot the word "licensing" in the final reiteration.
Sure that's true - but only on the minimum side. i.e. Windows licensing defaults to dual 8 core setups. IF you need more than that - you have to buy more.
Buying a single 10 core machine that will run Windows means if you ever need a second processor in there - you'll be required to buy 2 more two core license packs. Something to consider.
How often are people adding CPUs to servers? Is that something that generally happens? Of course @JaredBusch was faster then I was.
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@coliver said in VM host: dual CPU vs single CPU - same CPU performance rating:
@dashrender said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pmoncho said in VM host: dual CPU vs single CPU - same CPU performance rating:
@dustinb3403 said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pmoncho said in VM host: dual CPU vs single CPU - same CPU performance rating:
@jaredbusch said in VM host: dual CPU vs single CPU - same CPU performance rating:
@scottalanmiller said in VM host: dual CPU vs single CPU - same CPU performance rating:
@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
But for instance in my case 2 x E5-2630V2 (2x6 cores @ 2.5GHz) shows up as having about the same benchmark performance (single thread and multi thread) as 1 x E5-2670V2 (10 cores @ 2.5Ghz).
Comparing typical TDP: 2x6 cores is 2x80W=160W while 1x10 core is 115W.
This is partly why I push companies so hard to move to single proc servers. Often makes far more sense. There is way less overhead.
But in this case tool six scores versus Single Tencor you might as well get the dual processor advantages since you’re going to have to pay for the licensing anyway if he runs any Microsoft products at all
It seems to me, in these situations, software dictates hardware configuration negatively. That is frustrating if one wants to continue to use MS products. Choices, choices, choices!!
I would say the software isn't dictating the hardware, but the licensing terms that comes with the software is.
You are correct. I re-typed that a couple different times and forgot the word "licensing" in the final reiteration.
Sure that's true - but only on the minimum side. i.e. Windows licensing defaults to dual 8 core setups. IF you need more than that - you have to buy more.
Buying a single 10 core machine that will run Windows means if you ever need a second processor in there - you'll be required to buy 2 more two core license packs. Something to consider.
How often are people adding CPUs to servers? Is that something that generally happens? Of course @JaredBusch was faster then I was.
Never. RAM and disk, sure. Not CPU. Maybe if you buy a single proc server for a specific reason, the reassign it to be a busy SQL server or virtual host.
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Yeah I have to agree with the others, you buy a box and generally just fill everything because you're buying for what you need, not what you might need.
Purchasing a board that supports dual-cpu's and not using the other is just wasting money on an empty socket.
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@dustinb3403 said in VM host: dual CPU vs single CPU - same CPU performance rating:
Yeah I have to agree with the others, you buy a box and generally just fill everything because you're buying for what you need, not what you might need.
Purchasing a board that supports dual-cpu's and not using the other is just wasting money on an empty socket.
Except most vendors don't charge for the second socket. So that is very rarely the case.
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@pete-s said in VM host: dual CPU vs single CPU - same CPU performance rating:
Thanks guys.
I decided to go with the single 10-core CPU in this case as it would leave open the possibility of adding another CPU and set of memory if needed.
No licensing to consider in this particular case.
Keep in mind that the SL code of the existing CPU should be recorded as when it comes time to add the second CPU the same SL code CPU would need to be acquired.
There's a reason why Tier 1 charges huge coin to add a second CPU at a later date. They need to keep them on the shelf.
